The Legislative Branch

The legislative branch—called Congress—is divided into two parts, which are also called houses: the House of Representatives and the Senate.

The House of Representatives

The House of Representatives is meant to be “the people’s house,” or the part of government most responsive to public opinion. A state’s population determines how many representatives it will have in the House. Every member of the House represents a district within a state, and each district has roughly the same number of people. To make sure that the House accurately mirrors the changing population of the states, the Constitution mandates that a census be taken every ten years. Seats in the House are reapportioned, or reassigned, based on new census data to ensure that each House member represents about the same number of people. All 435 seats in the House go up for election every two years.

The Senate

The framers envisioned the Senate as a body of rational deliberation and statesmanship, not subject to the changing moods of the general population, which is why senators are elected every six years instead of every two years. Because the Senate was also intended to serve as a check on excessive democracy, only one-third of the Senate is elected at a time. Every state has two seats in the Senate, regardless of population.

The Powers of Congress

Article I, Section 8, of the Constitution outlines the powers of Congress. These specified powers are sometimes called the enumerated powers. The necessary and proper clause— commonly referred to as the elastic clause—also gives Congress the power to do whatever it deems “necessary and proper” to meet its constitutional mandate.

Example: The federal government spends billions of dollars each year on highway construction, which is not specifically mentioned in the Constitution. Congress justifies funding federal highways through the necessary and proper clause: Federal roads improve transportation, which, in turn, facilitates interstate commerce, a power the Constitution does specifically grant to Congress. In other words, funding federal roads is “necessary and proper” to regulate interstate commerce.

The Constitution gives Congress two important powers:

  1. The power to make laws: Only Congress can make laws. For a bill to become a law, it must first be approved by both the House and the Senate. The bill then goes to the president, who either signs it or vetoes it. Congress can override the president’s veto with a two-thirds vote in both houses.
  2. The power of the purse: Only Congress can tax citizens and spend money raised by taxes.

The Senate has some additional powers: It confirms presidential appointments to key federal offices, including federal judgeships. The Senate also ratifies all treaties.

The Constitution also lists prohibited powers, or things Congress may not do, including:

  • Passing an ex post facto law, which makes something illegal after it has already been done
  • Passing a bill of attainder, which declares a person guilty of a crime
  • Suspending the writ of habeas corpus, which requires police to charge everyone they arrest. Congress can only suspended this writ during times of national emergency.

The Executive Branch

The president heads the executive branch. According to the Constitution, the president has five powers:

  1. Conduct foreign policy
  2. Command the armed forces
  3. Appoint federal judges and other government officials
  4. Veto congressional bills
  5. Grant clemency

The Vice President

The other elected official within the executive branch is the vice president. The vice president has to following responsibilities:

  • Preside over the Senate and casts the deciding vote in case of a tie
  • Become president if the president dies, relinquishes the office, or is otherwise unable to perform the duties

The role of the vice president has evolved over time. Most vice presidents in the past were excluded from policymaking. After World War II, however, most presidents saw the value of including the vice president in discussions on foreign and domestic policy. Recent vice presidents, including Al Gore (1993–2001) and Dick Cheney (2001–2009), have been heavily involved in policymaking.

The Judicial Branch

The Constitution says little about the judicial branch. It names the Supreme Court as the highest court in the land and declares that the head of the court should be the chief justice. But Congress, and not the Constitution, determines the size and structure of the rest of the federal court system.

Appointment to the Bench

To become a federal judge, a person must be appointed by the president and approved by the Senate. Once in office, a judge can only be forced to leave if impeached and convicted. Otherwise, federal judges serve life terms.

Judicial Review

The courts’ power of judicial review—the power to declare laws and presidential actions unconstitutional—is not actually specified in the Constitution. The Supreme Court gave itself this power in the landmark case Marbury v. Madison (1803).

Example: The courts have exercised their power of judicial review throughout American history. The Supreme Court decision Brown v. Board of Education of Topeka, Kansas (1954), for example, ended segregation in public schools. The Supreme Court made use of judicial review by declaring racial segregation in public facilities unconstitutional.


Legislative Branch

Executive Branch

Judicial Branch

The power to make laws The power of the purseThe power to conduct foreign policy The power to command the armed forces The power to appoint federal judges and government officials The power to veto bills from Congress The power to grant pardons and clemencyThe Supreme Court is the most powerful court in the United States


Federalism is a system of government in which the national and state governments share power. The Constitution recognizes state governments and grants them certain powers, making federalism an implicit part of the Constitution.

Example: The national, or federal, government and the state governments share power in a variety of ways. The federal government, for example, has little power in the formation of education policy, leaving each individual state government to set its own education standards. State governments also reflect the political ideologies of their constituents, which is why different states have different laws regarding smoking, capital punishment, euthanasia, gun control, and so on.

Changing the Constitution

Article V of the Constitution explains how Americans can change the Constitution. A change in the Constitution is called an amendment. The framers intentionally made the process of changing the Constitution difficult because they wanted the Constitution to be stable. Although more than 11,000 amendments have been proposed since 1789, only twenty-seven have been approved, or ratified.

Changing the Constitution is a two-step process:

  1. An amendment must be proposed by either a two-thirds vote in both houses of Congress or by conventions called in two-thirds of the states.
  2. The amendment must then be ratified by either the approval of three-fourths of the state legislatures or by special ratifying conventions held in three-fourths of the states.

Informal Methods of Changing the Constitution

Even though only twenty-seven amendments have been ratified, the Constitution has changed in other ways. For example, Congress has given the president the responsibility of submitting a budget. The president has also entered into executive agreements with foreign leaders without getting prior approval or treaty ratification from the Senate. By far the biggest informal change to the Constitution has been the Supreme Court’s assertion of the power of judicial review.

The Bill of Rights

Many states ratified the Constitution in 1788 and 1789 on the condition that Congress amend it to guarantee certain civil liberties. James Madison drafted these first ten amendments himself, which collectively became known as the Bill of Rights. The Bill of Rights safeguards some specific rights of both the American people and the states. The table on the next page summarizes the twenty-seven amendments to the Constitution.



Date of Ratification


1st1791Grants freedoms of religion, speech, press, petition, and assembly
2nd1791Grants the right to bear arms
3rd1791Forbids the quartering of soldiers in citizens’ houses
4th1791Grants freedom from unreasonable searches and seizures
5th1791Grants the right against self-incrimination, of trial by jury, and of protection of private property
6th1791Grants the right to an attorney in any criminal case
7th1791Grants the right to a trial by jury in civil cases
8th1791Bans excessive bail and cruel and unusual punishment
9th1791States that the people’s rights are not limited to those explicitly listed in the Constitution
10th1791States that the states’ rights are not limited to those explicitly listed in the Constitution
11th1798Limits the jurisdiction of federal courts
12th1804Changes the rules for electing the vice president
13th1865Abolishes slavery
14th1868Defines American citizenship
15th1870Extends the right to vote to all male citizens
16th1913Allows Congress to levy income taxes
17th1913Allows people to elect their senators directly
18th1919Prohibits the manufacture, sale, and transport of liquor
19th1920Extends the right to vote to all female citizens
20th1933Changes the start date of presidential and congressional terms; outlines presidential succession
21st1933Repeals Prohibition
22nd1951Sets a two-term limit on presidents
23rd1961Gives Washington, D.C., electoral votes
24th1964Outlaws poll taxes
25th1967Changes the order of succession to the presidency
26th1971Extends the right to vote to all eighteen-year-old citizens
27th1992Limits congressional pay raises

Popular pages: The Founding and the Constitution